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From:   Alexander Potapenko <glider@google.com>
Date:   Fri, 22 Sep 2023 09:48:41 +0200
Message-ID: <CAG_fn=U0gcMpmTsfir27w4BwLS4Cp+kHa-CWqS5fX-9RjMCJcw@mail.gmail.com>
Subject: Re: [PATCH v4 1/5] lib/bitmap: add bitmap_{set,get}_value()
To:     Yury Norov <yury.norov@gmail.com>
Cc:     catalin.marinas@arm.com, will@kernel.org, pcc@google.com,
        andreyknvl@gmail.com, andriy.shevchenko@linux.intel.com,
        linux@rasmusvillemoes.dk, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, eugenis@google.com,
        syednwaris@gmail.com, william.gray@linaro.org,
        Arnd Bergmann <arnd@arndb.de>
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> Either way, whatever we decide, let's stay clear with our intentions
> and mention explicitly that tail bits are either must be zero, or
> ignored.
>
> Alexander, can you add the snippet above to the comments for the
> bitmap_write() and bitmap_read(), as well as in the test? Also, if we
> decide to clear tail of the input value, would BITMAP_LAST_WORD_MASK()
> generate better code than GENMASK(nbits - 1, 0) does?

Added the snippet above to bitmap_write(). I think however it is
obvious that bitmap_read() reads only nbits?

> Commets are very appreciated.
>
> Thanks,
> Yury


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Alexander Potapenko
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